Composition for display sealing material, organic protection layer comprising same, and display device comprising same

ABSTRACT

The present invention relates to a composition for a display sealing material having a photopolymerization initiator and a photocurable monomer, the photocurable monomer comprising: a monomer not having the aromatic hydrocarbon group; and a monomer having two or more substituted or unsubstituted phenyl groups of chemical formula 1, wherein about 5 wt % to about 45 wt % of the monomer having two or more substituted or unsubstituted phenyl groups is comprised on the basis of the photocurable monomer and about 55 wt % to about 95 wt % of the monomer not having the aromatic hydrocarbon group is comprised on the basis of the photocurable monomer.

CROSS REFERENCE TO RELATED APPLICATIONS

This is the U.S. national phase application based on PCT Application No.PCT/KR2015/003614, filed Apr. 10, 2017, which is based on Korean PatentApplication No. 10-2014-0148655, filed Oct. 29, 2014, and Korean PatentApplication No. 10-2015-0050505, filed Apr. 9, 2015, the entire contentsof all of which are hereby incorporated by reference.

TECHNICAL FIELD

The present invention relates to a composition for display sealingmaterial, an organic protection layer including the same, and a displaydevice including the same.

BACKGROUND ART

Organic electroluminescent devices used in optical display apparatusescan suffer from degradation or deterioration in properties by theenvironments such as moistures or gases. Specifically, the interfacebetween a metal field and an organic emitting layer will be delaminatedowing to moistures. Furthermore, high resistance will occur due to theoxidation of the metal, and organic materials themselves will bedeteriorated by moistures or oxygen. Moreover, the organic materials andelectrode materials will experience the oxidation by outgases fromexternal or internal environments, and the organic electroluminescentdevice may have reduced luminous properties. Thus, the organicelectroluminescent device must be encapsulated with an encapsulatingcomposition to protect it from moistures or oxygen.

The organic electroluminescent device has been encapsulated in amultilayer structure in which a inorganic protection layer and anorganic protection layer are formed. The inorganic protection layer maybe formed by a plasma deposition process, which can cause the organicprotection layer to be etched by plasma. When the organic protectionlayer is etched, the encapsulating function of the organic protectionlayer can be damaged. Thus, the organic light emitting device can sufferfrom deterioration in luminous properties and reliability.

In this regard, the background of the present invention is disclosed inKorean Laid-Open Patent Publication No. 2011-0071039 A (LG Display).

DISCLOSURE Technical Problem

In one aspect, the present invention provides a composition for displaysealing material realizing an organic protection layer having highplasma resistance.

In another aspect, the present invention provides a composition fordisplay sealing material realizing an organic protection layer havingremarkably low moisture permeation and oxygen permeability.

In still another aspect, the present invention provides a compositionfor display sealing material realizing an organic protection layerhaving excellent transparency.

In still another aspect, the present invention provides a compositionfor display sealing material realizing an organic protection layerhaving low surface roughness leading to high surface smoothness.

In still another aspect, the present invention provides a compositionfor display sealing material realizing an organic protection layerprotecting the apparatus from the environments including moistures andgases to provide the apparatus with time-dependent reliability.

In still another aspect, the present invention provides a displayapparatus including a cured product of a composition for display sealingmaterial.

Technical Solution

In one aspect of the present invention, a composition for displaysealing material may include a photo-curable monomer and aphotopolymerization initiator, wherein the photo-curable monomer mayinclude a monomer not containing an aromatic hydrocarbon group; and amonomer containing two or more of substituted or unsubstituted phenylgroups, represented by Formula 1, and the monomer containing two or moreof substituted or unsubstituted phenyl groups may be present in anamount of from about 5 wt % to about 45 wt % in the photo-curablemonomer, and the monomer not containing the aromatic hydrocarbon groupmay be present in an amount of from about 55 wt % to about 95 wt % inthe photo-curable monomer.

(wherein A is a hydrocarbon having two or more of substituted orunsubstituted phenyl groups, or a hydrocarbon having a heteroatom andtwo or more of substituted or unsubstituted phenyl groups;

Z1 and Z2 are each independently represented by Formula 2; and

a and b are an inter of 0 to 2, respectively, and a+b is an inter of 1to 4)

(wherein * represents a linker site to a carbon atom on A;

X is a single bond, O, or S;

Y is a substituted or unsubstituted C1 to C10 linear alkylene group, ora substituted or unsubstituted C1 to C20 alkoxy group;

R1 is a hydrogen or a C1 to C5 alkyl group; and c is 0 or 1.

In still another aspect of the present invention, a display apparatusmay include a display member, and a composite protection layer formed onthe display member, wherein the composite protection layer may include ainorganic protection layer and an organic protection layer, and theorganic protection layer includes a cured product prepared of thecomposition for display sealing material.

Advantageous Effects

The composition of the present invention may realize an organicprotection layer having high plasma resistance.

The composition of the present invention may realize an organicprotection layer having remarkably low moisture permeation and oxygenpermeability.

The composition of the present invention may realize an organicprotection layer having excellent transparency.

The composition of the present invention may realize an organicprotection layer having low surface roughness leading to high surfacesmoothness.

The composition of the present invention may realize an organicprotection layer protecting the apparatus from the environmentsincluding moistures and gases to provide the apparatus withtime-dependent reliability.

DESCRIPTION OF DRAWINGS

FIG. 1 is a cross-sectional view of a display apparatus according to oneembodiment of the present invention.

FIG. 2 is a cross-sectional view of a display apparatus according toanother embodiment of the present invention.

BEST MODE

Embodiments of the present invention will now be described in detail. Itshould be understood that the present invention is not limited to thefollowing embodiments and may be embodied in different ways. Althoughsome parts of elements is described for the convenience of thedescription, those skilled in the art readily may understand the otherparts of elements. In the drawings, width and thickness of the elementscan be expressed in a magnified form and some of irrelevant elements canbe omitted for clarity. In addition, the spirits of the presentinvention may be embodied in various other forms by those skilled in theart without departing the technical sprits of the present invention.

As used herein, terms such as “upper” and “lower” are defined withreference to the accompanying drawings. Thus, it will be understood thatthe term “upper surface” can be used interchangeably with the term“lower surface.” The term “on” encompasses both that one element isdisposed “directly on” another structure, and that the other structurecan be interposed. Meanwhile, the term “directly on” means that theother structure is not interposed.

As used herein, the term “(meth)acryl” refers to an acryl and/or amethacryl.

As used herein, the term “substituted”, unless otherwise stated, meansthat at least one hydrogen atom among functional groups is substitutedwith a hydroxyl group, a nitro group, an imino group (═NH, ═NR, whereinR is a C1 to C10 alkyl group), an amidino group, a hydrazine or ahydrazone group, a carboxyl group, a C1 to C20 alkyl group, a C6 to C30aryl group, a C3 to C30 heteroaryl group, or a C2 to C30heterocycloalkyl group.

As used herein, the term “heteroatom” means any atom selected from agroup of consisting of N, O, S and P, and the term “hetero” means that acarbon atom is substituted with any one atom selected from a group ofconsisting of N, O, S and P.

As used herein, the “plasma resistance” may be determined depending onthe etching rate to be etched when a cured product of an encapsulatingcomposition is subjected to a plasma treatment. Lower etching raterepresents higher plasma resistance.

As used herein, the “alkylene group” means a alkanediyl group attachedvia a saturated hydrocarbon without a double bond between(meth)acrylates at each terminal. Furthermore, the number of the carbonatom of the alkylene group means the number of the carbon atom of thealkylene group itself except the carbon atom in the di(meth)acrylategroup.

In one aspect of the present invention, a composition for displaysealing material may include a photo-curable monomer and aphotopolymerization initiator.

The photo-curable monomer means a photo-curable monomer capable ofcuring reaction by a photopolymerization initiator. A non-siliconmonomer not containing a silicon (Si) atom may be used as thephoto-curable monomer. For example, it may be, but not limited to, amonomer consisted of an element selected from C, H, O, N and S. Thephoto-curable monomer may be synthesized by a typical synthesis method,or be a commercially available product.

Specifically, the composition for display sealing material according toone aspect of the present invention may include a photo-curable monomerand a photopolymerization initiator, and the photo-curable monomer mayinclude a monomer not containing an aromatic hydrocarbon group; and amonomer containing two or more of substituted or unsubstituted phenylgroups represented by Formula 1, and about 5 wt % to about 45 wt % ofthe monomer containing two or more of substituted or unsubstitutedphenyl groups in the photo-curable monomer and about 55 wt % to about 95wt % of the monomer not containing the aromatic hydrocarbon group in thephoto-curable monomer.

wherein A is a hydrocarbon having two or more of substituted orunsubstituted phenyl groups, or a hydrocarbon having a heteroatom andtwo or more of substituted or unsubstituted phenyl groups,

Z1 and Z2 are each independently represented by Formula 2, and

a and b are an inter of 0 to 2, respectively, and a+b is an inter of 1to 4.

wherein * represents a linker site to a carbon atom on A;

X is a single bond, O, or S;

Y is a substituted or unsubstituted C1 to C10 linear alkylene group, orsubstituted or unsubstituted C1 to C20 alkoxy group,

R¹ is a hydrogen or a C1 to C5 alkyl group; and c is 0 or 1.

In the formula, A is a hydrocarbon having two or more of substituted orunsubstituted phenyl groups, or a hydrocarbon having a heteroatom andtwo or more of substituted or unsubstituted phenyl groups. Thehydrocarbon having two or more of substituted or unsubstituted phenylgroups, or a hydrocarbon having a heteroatom and two or more ofsubstituted or unsubstituted phenyl groups means a hydrocarbon in whichtwo or more of substituted or unsubstituted phenyl groups are notcondensed but linked via a single bond, an oxygen atom, a sulfur atom, asubstituted or unsubstituted C1 to C5 alkyl group, a C3 to C6 alkylenegroup unsubstituted or substituted with a heteroatom, an ethenylenegroup, an ethynylene group, or a carbonyl group. For example, thehydrocarbon having two or more of phenyl groups, or a hydrocarbon havinga heteroatom and two or more of substituted or unsubstituted phenylgroups may include, but not limited to, a substituted or unsubstitutedbiphenyl group, a substituted or unsubstituted triphenylmethyl group, asubstituted or unsubstituted terphenyl group, a substituted orunsubstituted biphenylene group, a substituted or unsubstitutedterphenylene group, a substituted or unsubstituted quaterphenylenegroup, a substituted or unsubstituted 2-phenyl-2-(phenylthio)ethylgroup, a substituted or unsubstituted 2,2-diphenylpropane group, asubstituted or unsubstituted diphenylmethane group, a substituted orunsubstituted cumyl phenyl group, a substituted or unsubstitutedbisphenol F group, a substituted or unsubstituted bisphenol A group, asubstituted or unsubstituted biphenyloxy group, a substituted orunsubstituted terphenyloxy group, a substituted or unsubstitutedquaterphenyloxy group, a substituted or unsubstituted quinquephenyloxygroup, structural isomers thereof, and the like.

The monomer containing two or more of substituted or unsubstitutedphenyl groups may be prepared from mono(meth)acrylate, di(meth)acrylateor mixtures thereof. And the examples of the monomer containing two ormore of substituted or unsubstituted phenyl groups include, but notlimited to, 4-(meth)acryloxy-2-hydroxybenzophenone,ethyl-3,3-diphenyl(meth)acrylate, benzoyloxyphenyl (meth)acrylate,bisphenol A di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate,bisphenol F di(meth)acrylate, ethoxylated bisphenol F di(meth)acrylate,4-cumylphenoxyethylacrylate, ethoxylated bisphenylfluorene diacrylate,2-phenylphenoxyethyl (meth)acrylate, 2,2′-phenylphenoxyethyldi(meth)acrylate, 2-phenylphenoxypropyl(meth)acrylate,2,2′-phenylphenoxypropyl di(meth)acrylate,2-phenylphenoxybutyl(meth)acrylate, 2,2′-phenylphenoxybutyldi(meth)acrylate, 2-(3-phenylphenyl)ethyl (meth)acrylate,2-(4-benzylphenyl)ethyl (meth)acrylate, 2-phenyl-2-(phenylthio)ethyl(meth)acrylate, 2-(triphenylmethyloxy)ethyl (meth)acrylate,4-(triphenylmethyloxy)butyl(meth)acrylate,3-(biphenyl-2-yloxy)butyl(meth)acrylate,2-(biphenyl-2-yloxy)butyl(meth)acrylate,4-(biphenyl-2-yloxy)propyl(meth)acrylate,3-(biphenyl-2-yloxy)propyl(meth)acrylate,2-(biphenyl-2-yloxy)propyl(meth)acrylate,4-(biphenyl-2-yloxy)ethyl(meth)acrylate, 3-(biphenyl-2-yloxy)ethyl(meth)acrylate, 2-(4-benzylphenyl)ethyl(meth)acrylate,4,4′-di(acryloyloxymethyl)biphenyl, 2,2′-di(acryloyloxyethoxy)biphenyl,structural isomers thereof, or mixtures thereof. In addition, the(meth)acrylate described herein is constructed only as the examples, andnot limited thereto, and further includes all the acrylate related tothe structural isomers. For example, although 2,2′-phenylphenoxyethyldi(meth)acrylate is described as one example, the present inventionencompasses 3,2′-phenylphenoxyethyl di(meth)acrylate,3,3′-phenylphenoxyethyl di(meth)acrylate, and the like corresponding toits structural isomer.

In one embodiment, the monomer containing two or more of phenyl groupsmay be a mono(meth)acrylate of Formula 3.

wherein, R² is hydrogen or a methyl group, R³ is a substituted orunsubstituted linear C1 to C10 alkylene group or a substituted orunsubstituted C1 to C20 alkoxy group, and R⁴ is a hydrocarbon having twoor more of substituted or unsubstituted phenyl groups, or a hydrocarbonhaving a heteroatom and two or more of substituted or unsubstitutedphenyl groups.

For example, the hydrocarbon having two or more of substituted orunsubstituted phenyl groups, or a hydrocarbon having a heteroatom andtwo or more of substituted or unsubstituted phenyl groups means ahydrocarbon in which two or more of substituted or unsubstituted phenylgroups are not condensed but linked via a single bond, an oxygen atom, asulfur atom, a substituted or unsubstituted C1 to C3 alkyl group, a C3to C6 alkylene group unsubstituted or substituted with a heteroatom, anethenylene group, an ethynylene group, or a carbonyl group. For example,the hydrocarbon having two or more of phenyl groups, or a hydrocarbonhaving a heteroatom and two or more of substituted or unsubstitutedphenyl groups may include, but not limited to, a substituted orunsubstituted biphenyl group, a substituted or unsubstitutedtriphenylmethyl group, a substituted or unsubstituted terphenyl group, asubstituted or unsubstituted biphenylene group, a substituted orunsubstituted terphenylene group, a substituted or unsubstitutedquaterphenylene group, a substituted or unsubstituted2-phenyl-2-(phenylthio)ethyl group, a substituted or unsubstituted2,2-diphenylpropane group, a substituted or unsubstituteddiphenylmethane group, a substituted or unsubstituted cumyl phenylgroup, a substituted or unsubstituted bisphenol F group, a substitutedor unsubstituted bisphenol A group, a substituted or unsubstitutedbiphenyloxy group, a substituted or unsubstituted terphenyloxy group, asubstituted or unsubstituted quaterphenyloxy group, a substituted orunsubstituted quinquephenyloxy group, and the like.

In one embodiment, the monomer containing two or more of phenyl groupsmay be a di(meth)acrylate of Formula 4.

wherein, R⁵ and R⁹ are hydrogen or a methyl group, R⁶ and R⁸ are eachindependently a substituted or unsubstituted linear C1 to C10 alkylenegroup, or —R′O-(wherein R′ is a substituted or unsubstituted linear C₁to C₁₀ alkylene group), and R⁷ is a hydrocarbon having two or more ofsubstituted or unsubstituted phenyl groups, or a hydrocarbon having aheteroatom and two or more of substituted or unsubstituted phenyl groups

For example, the hydrocarbon having two or more of substituted orunsubstituted phenyl groups, or a hydrocarbon having a heteroatom andtwo or more of substituted or unsubstituted phenyl groups means ahydrocarbon in which two or more of substituted or unsubstituted phenylgroups are not condensed but linked via a single bond, an oxygen atom, asulfur atom, a substituted or unsubstituted C1 to C4 alkyl group, a C3to C6 alkylene group unsubstituted or substituted with a heteroatom, anethenylene group, an ethynylene group, or a carbonyl group. For example,the hydrocarbon may include, but not limited to, a substituted orunsubstituted biphenylene group, a substituted or unsubstitutedtriphenylmethylene group, a substituted or unsubstituted terphenylenegroup, a substituted or unsubstituted quaterphenylene group,2-phenyl-2-(phenylthio)ethylene group, 2,2-diphenylpropylene group,diphenylmethylene group, and the like.

In the formula 1, a and b are independently an integer of 0 to 2, anda+b is an integer of 1 to 4, and in one embodiment an integer of 1 or 2.

The monomer containing two or more of substituted or unsubstitutedphenyl groups may have a weight average molecular weight of about 100g/mol or more and about 1000 g/mol or less, particularly about 130 g/molor more and about 700 g/mol or less, and more particularly about 150g/mol or more and about 600 g/mol or less.

Within this range, it is possible to provide an encapsulant with highplasma resistance, low surface roughness, and improved transmittance.

The monomer containing two or more of substituted or unsubstitutedphenyl groups may be present in an amount of from about 5 wt % to about45 wt %, and in particular from about 10 wt % to about 40 wt % in totalweight of the photo-curable monomer. Within this range, it is possibleto achieve a viscosity suitable for forming the encapsulant andexcellent plasma resistance.

The photo-curable monomer may include a monomer not containing thearomatic hydrocarbon group.

The monomer not containing the aromatic hydrocarbon group may notcontain the aromatic hydrocarbon group, and comprise the monomer mayhave 1 to 20 groups selected from a vinyl group, an acryl group and amethacryl group as the photo-curable functional group. The monomer notcontaining the aromatic hydrocarbon group may not contain the aromatichydrocarbon group, specifically 1 to 6 groups, for example, 1 to 3, 1 to2, 1, or 2 groups selected from a vinyl group, an acryl group and amethacryl group as the photo-curable functional group.

According to the present invention, the monomer not containing thearomatic hydrocarbon group may have a weight average molecular weight ofabout 100 g/mol or more and about 500 g/mol or less, particularly, about130 g/mol or more and about 400 g/mol or less, and more particularlyabout 200 g/mol or more and about 300 g/mol or less. In this range ofthe weight average molecular weight of the monomer, the process may havean advantageous effect.

The monomer not containing the aromatic hydrocarbon group may include amono-functional monomer, a multi-functional monomer, or mixturesthereof, which have the photo-curable functional group.

Specifically, the monomer not containing the aromatic hydrocarbon groupmay be (meth)acrylate monomer. And the monomer not containing thearomatic hydrocarbon group may include, for example, an unsaturatedcarbonic acid ester having a C1 to C20 alkyl group, a C3 to C20cycloalkyl group, or a hydroxyl group and a C1 to C20 alkyl group; anunsaturated carbonic acid ester having a C1 to C20 amino alkyl group; aC1 to C20 saturated or unsaturated vinyl ester of carbonic acid; a vinylcyanide compound; an unsaturated amide compound; a mono-functional ormulti-functional (meth)acrylate of a monovalent alcohol or mutivalentalcohol, and the like. The “multivalent alcohol” means an alcohol havingtwo or more hydroxyl groups, and in particular, an alcohol having 2 to20 hydroxyl groups, preferably 2 to 10 hydroxyl groups, and morepreferably 2 to 6 hydroxyl groups.

In one embodiment, the (meth)acrylate monomer not containing thearomatic hydrocarbon group among the monomer not containing the aromatichydrocarbon group may be a mono (meth)acrylate, a di(meth)acrylate, atri(meth)acrylate, a tetra (meth)acrylate, and the like having asubstituted or unsubstituted C1 to C20 alkyl group, a substituted orunsubstituted C1 to C20 alkyl silyl group, a substituted orunsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstitutedC1 to C20 alkylene group, amine group, ethyleneoxide group, and the like

Specifically, it may include, but not limited to, an unsaturatedcarbonic acid ester including (meth)acrylic acid ester such as methyl(meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate,2-hydroxyethyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, hexyl(meth)acrylate, octyl (meth)acrylate, nonyl (meth)acrylate, decanyl(meth)acrylate, undecanyl (meth)acrylate, dodecyl (meth)acrylate,cyclohexyl (meth)acrylate, and the like; an unsaturated carbonic acidaminoalkyl ester such as 2-aminoethyl (meth)acrylate,2-dimethylaminoethyl (meth)acrylate, and the like; a saturated orunsaturated carbonic acid vinyl ester such as vinyl acetate, and thelike; vinyl cyanide compounds such as (meth)acrylonitrile, and the like;an unsaturated amide compounds such as (meth)acrylamide, and the like;ethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate,trimethylolpropane tri(meth)acrylate, 1,4-butanediol di(meth)acrylate,1,6-hexanediol di(meth)acrylate, octanediol di(meth)acrylate, nonanedioldi(meth)acrylate, decanediol di(meth)acrylate, undecanedioldi(meth)acrylate, dodecanediol di(meth)acrylate, neopentylglycoldi(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritoltri(meth)acrylate, pentaerythritol tetra(meth)acrylate,dipentaerythritol di(meth)acrylate, dipentaerythritol tri(meth)acrylate,dipentaerythritol tetra(meth)acrylate, dipentaerythritolpenta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, or mixturesthereof.

In one embodiment, the monomer not containing an aromatic hydrocarbongroup may include, as a non-aromatic compound not having an aromaticgroup, at least one of a mono(meth)acrylate having C1 to C20 alkylgroup, a mono(meth)acrylate having amine group, a di(meth)acrylatehaving a substituted or unsubstituted C1 to C20 alkylene group, adi(meth)acrylate having ethylene oxide group, and a tri(meth)acrylatehaving ethylene oxide group.

The mono(meth)acrylate having the substituted or unsubstituted C1 to C20alkyl group may include specifically, but not limited to, decyl(meth)acrylate, undecyl (meth)acrylate, lauryl (meth)acrylate, tridecyl(meth)acrylate, tetradecyl (meth)acrylate, pentadecyl (meth)acrylate,hexadecyl (meth)acrylate, heptadecyl (meth)acrylate, octadecyl(meth)acrylate, nonadecyl (meth)acrylate, arachidyl (meth)acrylate, ormixtures thereof.

The mono(meth)acrylate having the amine group may include, but notlimited to, 2-aminoethyl (meth)acrylate, 2-dimethylaminoethyl(meth)acrylate or mixtures thereof.

The di(meth)acrylate having the substituted or unsubstituted C1 to C20alkylene group may be, for example, di(meth)acrylate having C1 to C20alkylene group, or nonsilicone-based di(meth)acrylate having substitutedor unsubstituted long-chain alkylene group. If the encapsulatingcomposition includes the nonsilicone-based di(meth)acrylate havinglong-chain alkylene group, the composition may be used to form easily anorganic barrier layer on an organic light emitting device or aninorganic layer encapsulating the organic light emitting device by adeposition etc. The di(meth)acrylate having the substituted orunsubstituted C1 to C20 alkylene group may include, for example, but notlimited to, octanediol di(meth)acrylate, nonanediol di(meth)acrylate,decanediol di(meth)acrylate, undecanediol di(meth)acrylate, dodecanedioldi(meth)acrylate, or mixtures thereof. If the encapsulating compositionmay include a substituted or unsubstituted C1 to C20 alkylene group, thecomposition may have excellent photopolymerization rate and lowviscosity.

The di(meth)acrylate or tri(meth) acrylate having the ethylene oxidegroup may include specifically, but not limited to, ethylene glycoldi(meth)acrylate, triethylene glycol di(meth)acrylate,trimethylolpropane tri(meth)acrylate, or mixtures thereof.

The monomer not containing the aromatic hydrocarbon group may be presentin an amount of from about 55 wt % to about 95 wt %, and in particular,from about 60 wt % to about 90 wt % in total weight of the photo-curablemonomer. Within this range, it is possible to achieve a viscosity of thecomposition for display sealing material suitable for forming theencapsulant of the organic electroluminescent device.

The photopolymerization initiator may include, without limitation, atypical photopolymerization initiator capable of photo-curing reaction.For example, the photopolymerization initiator may include triazine,acetophenone, benzophenone, thioxanthone, benzoin, phosphorus, oxime, ormixtures thereof.

The triazine initiator may include, for example,2,4,6-trichloro-s-triazine,2-phenyl-4,6-bis(trichloromethyl)-s-triazine, 2-(3′,4′-dimethoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4′-methoxynapthyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(p-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine,2-(p-tollyl)-4,6-bis(trichloromethyl)-s-triazine,2-biphenyl-4,6-bis(trichloromethyl)-s-triazine,bis(trichloromethyl)-6-styryl-s-triazine,2-(naptho-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-methoxynaptho-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2,4-trichloromethyl(piperonyl)-6-triazine, 2,4-(trichloromethyl(4′-methoxystyryl)-6-triazine, or mixtures thereof.

The acetophenone initiator may include, for example, 2,2′-diethoxyacetophenone, 2,2′-dibutoxy acetophenone, 2-hydroxy-2-methylpropiophenone, p-t-butyl trichloro acetophenone, p-t-butyl dichloroacetophenone, 4-chloro acetophenone, 2,2′-dichloro-4-phenoxyacetophenone, 2-methyl-1-(4-(methylthio)phenyl)-2-morpholinopropane-1-one, 2-benzyl-2-dimethyl amino-1-(4-morpholinophenyl)-butan-1-one, or mixtures thereof.

The benzophenone initiator may include, for example, benzophenone,benzoyl benzoic acid, benzoyl benzoic acid methyl ester, 4-phenylbenzophenone, hydroxy benzophenone, acrylated benzophenone,4,4′-bis(dimethyl amino)benzophenone, 4,4′-dichlorobenzophenone.3,3′-dimethyl-2-methoxy benzophenone, or mixtures thereof.

The thioxanthone initiator may include, for example, thioxanthone,2-methyl thioxanthone, isopropyl thioxanthone, 2,4-diethyl thioxanthone,2,4-diisopropyl thioxanthone, 2-chloro thioxanthone, or mixturesthereof.

The benzoin initiator may include, for example, benzoin, benzoin methylether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutylether, benzyl dimethyl ketal, or mixtures thereof.

The phosphorus initiator may include, for example, bis benzoyl phenylphosphine oxide, benzoyl diphenyl phosphine oxide, or mixtures thereof.

The oxime initiator may include, for example,2-(o-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione and1-(o-acetyloxime)-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone,or mixtures thereof.

The photopolymerization initiator may be present in an amount of fromabout 0.1 parts by weight to about 20 parts by weight based on 100 partsby weight of the photo-curable monomer and the photopolymerizationinitiator in the composition for display sealing material. Within thisrange, the photo-curing may occur sufficiently upon exposure, and thedecrease in transmittance owing to the unreacted initiator residingafter photo-curing may be prevented. Specifically, thephotopolymerization initiator may be present in an amount of about 0.5to about 10 parts by weight, and in particular, from about 1 to about 8parts by weight. In addition, the photopolymerization initiator may bepresent in an amount of from about 0.1 wt % to about 10 wt %, and inparticular, about 0.1 wt % to about 8 wt %, on the solid contents, inthe composition for display sealing material. Within this range, thephoto-curing may occur sufficiently, and the decrease in transmittanceowing to the unreacted residual initiator may be prevented.

Furthermore, instead of the photopolymerization initiator, the photoacid generator or the photopolymerization initiator such as cabazole,diketone, sulfonium, iodonium, diazo, biimidazole, and the like may beused.

In another embodiment of the present invention, the composition fordisplay sealing material may further include an antioxidant.

The antioxidant may improve the thermal stability of the encapsulatinglayer. The antioxidant may include, but not limited to, at least oneselected from the group consisting of phenol, quinone, amine andphosphite. For example, the antioxidant may include, for example,tetrakis[methylene(3,5-di-t-butyl-4-hydroxyhydrocinnamate)]methane,tris(2,4-di-tert-butylphenyl)phosphite, and the like.

The antioxidant may be present in an amount of from about 0.01 parts byweight to about 3 parts by weight, and in particular, about 0.01 partsby weight to about 1 part by weight in about 100 parts by weight of thephoto-curable monomer and the photopolymerization initiator in thecomposition for display sealing material. Within this range, it ispossible to achieve excellent thermal stability.

The composition for display sealing material according to otherembodiment of the present invention may further include a thermalstabilizer. As a result, the composition for display sealing materialaccording to other embodiment of the present invention may suppress theviscosity change at an ambient temperature. In addition, the compositionmay have high light transmittance and photopolymerization rate over theencapsulating composition not including thermal stabilizer, and lowplasma etching rate. The composition is the same as the composition fordisplay sealing material according to one embodiment of the presentinvention except that it further includes the thermal stabilizer.Hereinafter, details of the thermal stabilizer will be described.

The thermal stabilizer included in the composition serves to suppressthe viscosity change of the composition at an ambient temperature, andmay be any thermal stabilizer typically used. For example, the thermalstabilizer may include a sterically hindered phenolic thermalstabilizer. Specifically, the thermal stabilizer may include, but notlimited to, at least one of poly(di-cyclopentadiene-co-p-cresol),octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate,2,6-di-tert-butyl-4-methylphenol,2,2′-methano-bi(4-methyl-6-tert-butyl-phenol),6,6′-di-tert-butyl-2,2′-thiodi-p-cresol,tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanurate,triethylneglycol-bis(3-tert-butyl-4-hydroxy-5-methylphenyl),4,4′-thiobis(6-tert-butyl-m-cresol),3,3′-bis(3,5-di-tert-butyl-4-hydroxyphenyl)-N,N′-hexamethylene-dipropionamide,pentaerythritoltetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate,stearyl-3,5-di-tert-butyl-4-hydroxyphenylpropionate,pentaerythritoltetrakis1,3,5-tris(2,6-di-methyl-3-hydroxy-4-tert-benzyl)isocyanurate,1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, and1,3,5-tris(2-hydroxyethyl)isocyanurate-tris(3,5-di-tert-butylhydroxyphenylpropionate).

The thermal stabilizer may be present in an amount of about 2000 ppm orless, for example, about 0.01 ppm to about 2000 ppm, for example, about100 ppm to about 1000 ppm, on the solid contents, based on the totalweight of the photo-curable monomer and the photopolymerizationinitiator in the composition for display sealing material. Within thisrange, the thermal stabilizer may improve storage stability andprocessability of the encapsulating composition in liquid phase.

The composition for display sealing material may be subjected to UVcuring at a dose of about 10 mW/cm² to about 500 mW/cm² for about 1 toabout 100 seconds.

The composition for display sealing material may have a plasma etchingrate represented by Equation 1 of about 400 nm/min or less and aroughness of about 2 nm or less:Plasma etching rate(nm/min)=(T0−T1)/M  [Equation 1]

Where in equation 1, T0 is a thickness (nm) of a sample prepared byapplying the composition for display sealing material on a substrate bya spray, and UV curing at a dose of about 100 mW/cm² for about 10seconds, T1 is a thickness (nm) of the prepared sample after beingsubjected to a plasma treatment under the conditions of ICP (inductivelycoupled plasma) power of 2500 W, RF (radio frequency) power of 300 W, DCbias of 200 V, argon (Ar) flow rate of 50 sccm, and pressure of 10 mTorrfor about 1 min, each T0 and T1 are the thickness exclusive of thethickness of the substrate, and M is a time of the plasma treatment(min).

It is possible to provide the organic protection layer with remarkablylow plasma etching rate, which represents the damage of the organicprotection layer caused by the plasma treatment, using the photo-curablemonomer having plasma etching rate after curing, when the organicprotection layer is formed on the organic electroluminescent device orthe inorganic protection layer formed on the organic electroluminescentdevice. In particular, the plasma etching rate may be about 400 nm/minor less, particularly about 10 nm/min to about 390 nm/min, and moreparticularly about 10 nm/min to about 385 nm/min. The plasma etchingrate, represented by equation 1, of more than about 400 nm/min may leadto the increase in damage of the organic protection layer and thedecrease in reliability of the device.

The surface roughness is a roughness of deposited surface, measured forits flection when the composition for display sealing material isdeposited on the substrate. The lower surface roughness may attribute tothe smoothness of the display.

The roughness used herein may be determined by the general method wellknown to those skilled in the art according to roughness measurements.For example, it may be determined using an atomic force microscope(AFM). According to the present invention, the surface roughness(roughness of the deposited surface), measured using AFM, may bepreferably about 2 nm or less, and in particular from about 0 nm toabout 2 nm, from about 0 nm to about 1.9 nm, from about 0 nm to about1.85 nm. According to the present invention, if the surface roughness isabout 2 nm or less, then it is possible to provide the organicprotection layer with the smooth surface and the inorganic protectionlayer with the smooth surface after depositing the organic protectionlayer. If the surface roughness is more than about 2 nm, then theorganic protection layer may be provided with the unsmooth surface, andwhen the inorganic protection layer is deposited on the surface of thecured product, the inorganic protection layer may be easily broken.

The generated amount of the outgases may be about 2000 ppm or less inthe display apparatus including the organic protection layer formed fromthe composition for display sealing material. Within this range, it ispossible to increase the reliability since the element of the apparatushas long self-life. Specifically, the amount may be about 10 ppm toabout 1000 ppm.

The generated amount of the outgases may be determined by a typicalmethod. For example, the composition for display sealing material may beapplied on the glass substrate, and subjected to UV curing at a dose ofabout 100 mW/cm² for about 10 seconds to prepare a cured specimen havinga about 5 μm thick film. A TD-GC/MS (TD: JTD505III, GC/MS: Clarus 600,Perkin Elmer) equipment may be used to determine the amount of theoutgas captured on certain area (1×5 cm²), generated by heating the 5 μmthick film from about 40° C. to about 320° C. at a rate of about 10°C./min.

The composition for display sealing material may have a color coordinateYI (ASTM D1925) of about 0.5 or less, and in particular, from about 0.1to about 0.5 after curing. Within this range, the encapsulant of thedisplay may be transparent, and transmit a light similar to a whitelight and thus applied to the display.

The color coordinate may be determined by a typical method. For example,the composition for display sealing material may be applied on the glasssubstrate, and subjected to UV curing at a dose of about 100 mW/cm² forabout 10 seconds to prepare a cured specimen having a about 5 μm thickfilm. A UV-visible spectrophotometer (UV-2450, SHIMADZU) analysisequipment may be used to determine the transmittance of the about 5 μmthick film at a wavelength of 300 nm to 800 nm and calculate the colorcoordinate YI (ASTM D1925).

The composition for display sealing material may have a totaltransmittance of about 90% or more and about 100% or less, and inparticular, 95% or more and 100% or less after curing, and thus providethe transparent organic protection layer.

The total transmittance and a haze may be determined using a hazemeter(NDH-5000, Nippon Denshoku) at a wavelength of about 400 nm to about 700nm according to ASTM D1003-95 5.

The composition for display sealing material may be applied to the frontside to be emitted, and should not exhibit any color and be transparent.If the encapsulant of the display exhibit any color, the light generatedfrom the light source of the display penetrates the encapsulantpositioned in the front side and then leads to the distortion of thecolor to be realized because the color coordinate is discrepant.Furthermore, if the transparency is lower, the light emitted to thefront side may have reduced efficacy and reduce the sharpness of thedisplay.

In some embodiments of the present invention, the composition fordisplay sealing material may be used as the encapsulant of the organicelectroluminescent device. Specifically, the organic electroluminescentdevice may be damaged from the surrounding environments, for example,liquids or gases, particularly moistures or oxygen, or chemicals used inthe process of preparing the apparatus including the organicelectroluminescent device. Furthermore, to prevent the deterioration ofthe properties, the composition may be used as the encapsulant forforming the organic protection layer to prevent the organicelectroluminescent device from the surrounding environments.

In some embodiments of the present invention, the composition fordisplay sealing material may be used as the encapsulant of the devicemember. Specifically, the device member may be damaged from thesurrounding environments, for example, liquids or gases, particularlymoistures or oxygen, or chemicals used in the process of preparing theapparatus including the organic electroluminescent device. Furthermore,to prevent the deterioration of the properties, the composition may beused as the encapsulant for forming the organic protection layer toprevent the device member from the surrounding environments. The devicemember may include, for example, a flexible organic electroluminescentdevice, an organic electroluminescent device, and the like.

In some embodiments of the present invention, the composition fordisplay sealing material may be used to form the organic protectionlayer formed on the organic electroluminescent device, or the organicprotection layer formed on the inorganic protection layer formed on theorganic electroluminescent device. The organic protection layer may beformed by, but not limited to, a deposition, an ink jet, and the like.

According to still another aspect of the present invention, a displayapparatus may include a device member, and a composite protection layerformed on the device member, wherein the composite protection layer mayinclude a inorganic protection layer and an organic protection layer,and the organic protection layer may be prepared of a composition fordisplay sealing material according to some aspects of the presentinvention.

Hereinafter, a display apparatus according to one aspect of presentinvention will be described referring to FIG. 1.

FIG. 1 is a cross-sectional view of a display apparatus according to oneaspect of the present invention. A display apparatus 100 according toone aspect may include a substrate 10, a device member 20 formed on thesubstrate 10, and a composite protection layer 30, formed on the devicemember 20, including a inorganic protection layer 31 and an organicprotection layer 32, wherein the inorganic protection layer 31 may beformed in contact with the device member 20, and the organic protectionlayer 32 may be prepared of a composition for display sealing materialaccording to aspects of the present invention.

As used herein, the display means a light emitting diode (LED), anorganic light emitting diode (OLED), an light instrument, an lightinstrument include both OLED light instrument and LED light instrument,as well as the display apparatus used in the art.

The display apparatus may include, but not limited to, a flexibleorganic electroluminescent device, an organic electroluminescent device,and the like.

The substrate 10 is not particularly limited, and may include, forexample, a transparent glass, plastic film, silicon or metal substrate,and the like.

The device member 20 may include, for example, an organicelectroluminescent device, and include a first electrode, a secondelectrode, an organic emitting layer between the first electrode and thesecond electrode, and the organic emitting layer may be a layer in whicha hole injection layer, a hole transporting layer, an emitting layer, anelectron transporting layer, an electron injection layer, withoutlimitation, are laminated sequentially.

The composite protection layer 30 may include the inorganic protectionlayer 31 and the organic protection layer 32, and the inorganicprotection layer 31 and the organic protection layer 32 may be preparedof different components and serve individually as the encapsulant of thedevice member.

The inorganic protection layer 31 may have the different component fromthat of the organic protection layer 32, and complement the effect ofthe organic protection layer 32. The inorganic protection layer 31 maybe prepared of the inorganic materials having excellent lighttransmittance and barrier property of moistures and/or oxygen. Forexample, the inorganic protection layer 31 may include metals,non-metals, intermetallic compounds or alloys, non-intermetalliccompounds or alloys, metal or non-metal oxides, metal or non-metalfluorides, metal or non-metal nitrides, metal or non-metal carbides,metal or non-metal oxynitrides, metal or non-metal borides, metal ornon-metal oxyborides, metal or non-metal silicides, or mixtures thereof.The metal may include, but not limited to, at least in of semimetals,basic metals, transition metals and lanthanide metals, specifically themetal may include at least one of silicon (Si), aluminum (Al), selenium(Se), zinc (Zn), antimony (Sb), indium (In), germanium (Ge), tin (Sn),bismuth (Bi), transition metal, lanthanide metal, and the like.Specifically, the inorganic protection layer may include silicon oxides(SiOx), silicon nitrides (SiNx), silicon oxynitrides (SiOxNy), ZnSe,ZnO, Sb₂O₃, AlOx such as Al₂O₃, and the like, In₂O₃, or SnO₂, wherein xand y are each 1 to 5.

The inorganic protection layer 31 may be deposited by a plasma process,a vacuum process, for example a sputtering, a chemical vapor deposition,a plasma-enhanced chemical vapor deposition, an evaporation, asublimation, an electron cyclotron resonance-plasma chemical vapordeposition and combinations thereof.

The thickness of the inorganic protection layer 31 is not particularlylimited but may be 100 Å to 2000 Å. Within this range, the encapsulatingeffect may be enhanced.

The organic protection layer 32 may be prepared by a deposition, an inkjet, a screen printing, a spin coating, a blade coating, a curing, aloneor in combination thereof, of the composition for display sealingmaterial according to aspects of the present invention. For example, thecomposition for display sealing material may be coated into about 1 μmto about 50 m thickness, and subjected to UV curing a dose of about 10mW/cm² to about 500 mW/cm² for about 1 to about 100 seconds.

Having not described in FIG. 1, the organic protection layer and theinorganic protection layer may be deposited alternately into 3 or morelayers. If the organic protection layer is deposited between 2 or moreof inorganic protection layers, it is possible to ensure the smoothnessof the inorganic protection layer, and prevent the defect of theinorganic protection layer from being transmitted to the other inorganicprotection layer. In addition, if the inorganic protection layer isdeposited between 2 or more of organic protection layers, it is possibleto enhance or increase the effect of encapsulating the apparatus.

The composite protection layer 30 may include the inorganic protectionlayer 31 and the organic protection layer 32 alternately, provided thatthe total number of the inorganic protection layer 31 and the organicprotection layer 32 is not limited. The total number of the inorganicprotection layer 31 and the organic protection layer 32 may depend onthe level of the permeability resistance to oxygen and/or moisturesand/or water vapor and/or chemicals. For example, the total number ofthe inorganic protection layer 31 and the organic protection layer 32may be 10 or less, for example, 2 to 7. Specifically, seven layers suchas the inorganic protection layer/the organic protection layer/theinorganic protection layer/the organic protection layer/the inorganicprotection layer/the organic protection layer/the inorganic protectionlayer sequentially may be formed.

The display apparatus may have the generated amount of the outgases ofabout 2000 ppm or less. Within this range, the display member may havelong self-life and high reliability. In particularly, the amount may beabout 10 ppm to about 1000 ppm.

Hereinafter, a display apparatus according to another aspect of presentinvention now will be described referring to FIG. 2. FIG. 2 is across-sectional view of a display apparatus according to another aspectof the present invention.

Referring to FIG. 2, a display apparatus 200 according to another aspectmay include a substrate 10, a device member 20 formed on the substrate10, and a composite protection layer 30, formed on the device member 20,including a inorganic protection layer 31 and an organic protectionlayer 32, wherein the inorganic protection layer 31 may encapsulate aninternal space 40 in which the device member 20 is received, and theorganic protection layer 32 may be prepared of a composition for displaysealing material according to aspects of the present invention. Theorganic light emitting device display according to another aspect of thepresent invention is substantially same as the display according to oneaspect of the present invention except that the inorganic protectionlayer 31 is not contact with the device member 20 and therefore.

MODE FOR INVENTION

Hereinafter, the present invention will be described in more detail withreference to some examples. However, it should be understood that theseexamples are provided for illustration only and are not to be in any wayconstrued as limiting the present invention. A description of detailsapparent to those skilled in the art will be omitted for clarity.

Preparative Example 1

To a 3000 ml flask equipped with a cooling pipe and a stirrer, 300 ml ofdichloromethane (Sigma-Aldrich) was charged, and 200 g of 4-hydroxybutylacrylate (Shin-Nakamura Chemical Co., Ltd.) and 168 g of triethylaminewere added. After the temperature in the flask was allowed to cool to 0°C., a solution of 278 g of p-toluene sulfonyl chloride (Sigma-Aldrich)in 500 ml of dichloromethane was dropwise added for 2 hours whilestirring. Thereafter, the solution was stirred for 5 hours again and theresidual solvents were removed by a distillation. Then, 300 g of theobtained compound was added to 1000 ml of acetonitrile (Sigma-Aldrich),and 220 g of potassium carbonate (Sigma-Aldrich) and 141 g of2-phenylphenol (Sigma-Aldrich) were added while stirring at 80° C. Theresidual solvents and reaction residues were removed to afford acompound of formula 5 (molecular weight: 296.36) having a purity of 93%as determined by HLPC.

Preparative Example 2

To a 2000 ml flask equipped with a cooling pipe and a stirrer, 600 ml ofdichloromethane (manufacturer: Sigma-Aldrich) was charged, 58.8 g ofhydroxyethyl methacrylate (Sigma-Aldrich) and 52.2 g of triethylamine(Sigma-Aldrich) were added while stirring at 0° C. and 100 g oftriphenyl chloromethane (Sigma-Aldrich) was slowly added. After thetemperature in the flask was allowed to increase to 25° C., the solutionwas stirred for 4 hours. Then, dichloromethane was removed by a vacuumdistillation and the solution was subjected to a chromatography througha silica gel column to obtain a compound of formula 6 (124 g) having apurity of 97% as determined by HLPC.

Preparative Example 3

To a 2000 ml flask equipped with a cooling pipe and a stirrer, 800 ml ofacetonitrile (Fisher) was charged, 180 g of potassium carbonate(Aldrich) and 108 g of acrylic acid were added while stirring at 0° C.,and 150 g of 4,4′-bis(chloromethyl) biphenyl (TCI) was slowly added.After the temperature in the flask was allowed to increase to 70° C.,the solution was stirred for 12 hours. Then, acetonitrile was removed bya vacuum distillation and the solution was subjected to a chromatographythrough a silica gel column to obtain a compound of formula 7 (177 g)having a purity of 97% as determined by HLPC.

Preparative Example 4

To a 3000 ml flask equipped with a cooling pipe and a stirrer, 300 ml ofdichloromethane (Sigma-Aldrich) was charged, 200 g of hydroxylethylacrylate (Shin-Nakamura Chemical Co., Ltd.) and 168 g of trimethylaminewere added. After the temperature in the flask was allowed to decreaseto 0° C., the solution in which 278 g of p-toluene sulfonyl chloride(Sigma-Aldrich) was dissolved in 500 ml of dichloromethane was drop-wiseadded for 2 hours while stirring. After stirring for 5 hours again, theremaining solvent was removed by distillation. 300 g of the obtainedcompound was added to 1000 ml of acetonitrile (Sigma-Aldrich), and 220 gof potassium carbonate (Sigma-Aldrich) and 141 g of 2-phenylphonol(Sigma-Aldrich) were added again, and stirred at 80° C. Then, theremaining solvent and the reaction residues were removed to obtain acompound of formula 8 (molecular weight 296.36) having a purity of 93%as determined by HLPC.

Preparative Example 5

To a 3000 ml flask equipped with a cooling pipe and a stirrer, 300 ml ofdichloromethane (Sigma-Aldrich) was charged, 400 g of hydroxylethylacrylate (Shin-Nakamura Chemical Co., Ltd.) and 168 g of trimethylaminewere added. After the temperature in the flask was allowed to decreaseto 0° C., the solution in which 278 g of p-toluene sulfonyl chloride(Sigma-Aldrich) was dissolved in 500 ml of dichloromethane was drop-wiseadded for 2 hours while stirring. After stirring for 5 hours again, theremaining solvent was removed by distillation. 300 g of the obtainedcompound was added to 1000 ml of acetonitrile (Sigma-Aldrich), and 220 gof potassium carbonate (Sigma-Aldrich) and 141 g of 2-phenylphonol(Sigma-Aldrich) were added again, and stirred at 80° C. Then, theremaining solvent and the reaction residues were removed to obtain acompound formula 9 (molecular weight 382.41) having a purity of 91% asdetermined by HLPC.

Preparative Example 6

To a 1000 ml flask equipped with a cooling pipe and a stirrer, 8.2 g ofzinc perchlorate (Sigma-Aldrich) was added to 100 g of benzene thiol and200 ml of dichloromethane (Sigma-Aldrich) while stirring, and 109.05 gof styrene oxide (Sigma-Aldrich) was drop-wise slowly added to allow thereaction to proceed at an ambient temperature. After 4 hours, theinorganic materials were removed using water and dichloromethane, andthe remaining solvent was removed to obtain 192 g of a first product. Toa 2000 ml flask, 150 g of the first product, 70.31 g of trimethylamine(Sigma-Aldrich) and 500 ml of dichloromethane were added and stirred at0° C., and 64.84 g of acryloyl chloride (Sigma-Aldrich) was drop-wiseslowly added to allow the reaction to proceed. After adding, thetemperature was slowly increased to the ambient temperature, and themixture was stirred for 4 hours again. After reaction, n-hexane (daejungchemicals & metals co.) was purified to remove salts and impurities, andthe remaining solvent was distillated under reduced pressure to obtain acompound of formula 10 (molecular weight 284.37) having a purity of 85%as determined by HLPC.

The details of components used in Examples and Comparative Examples areas follow:

(A) Monomer not containing an aromatic hydrocarbon group:

(a1) Dodecanediol dimethacrylate (Satomer)

(a2) Triethylene glycol dimethacrylate (BASF SE)

(a3) Trimethylolpropane triacrylate (BASF SE)

(a4) 2-Dimethylaminoethyl acrylate (ACROS)

(B) Monomer containing two or more of substituted or unsubstitutedphenyl groups:

(b1) Monomer of Preparative Example 1

(b2) Monomer of Preparative Example 2

(b3) Monomer of Preparative Example 3

(b4) Monomer of Preparative Example 4

(b5) Monomer of Preparative Example 5

(b6) Monomer of Preparative Example 6

(b7) CP-011 (4-cumylphenoxyethyl acrylate, Hannong Chemicals, Inc.)

(b8) Bisphenol A dimethacrylate (Aldrich)

(b9) BPM-102 (Bisphenol A ethoxylated (10) methacrylate, HannongChemicals, Inc.)

(b10) Bisphenol F ethoxylated (2) diacrylate (Aldrich)

(C) Photo-initiator: phosphorus initiator (Darocur TPO, BASF SE)

Example 1

To 125 ml brown polypropylene bottle, 90 parts by weight of (a1), 10parts by weight of (b1) and 5 parts by weight of (C) were charged, andstirred using a shaker for 3 hours to prepare a composition for displaysealing material of Example 1.

Examples 2 to 25 and Comparative Examples 1 to 15

The compositions were prepared in the same manner as in Example 1 exceptthat the kinds and amounts of the each component as shown in Tables 1 to3 were used.

Evaluation of Physical Property

(1) Plasma etching rate (%): A specimen including a 5 μm thick organicprotection layer was prepared by applying the composition for displaysealing material of Examples and Comparative Examples on 525±25 μm thicksilicon wafer by a spray, and was subjected to UV curing at a dose of100 mW/cm² for 10 seconds. The prepared specimen was plasma treated withan argon gas using an ICP dry etcher (Plasma lab system 133. Oxfordinstruments) under conditions of ICP power 2500 W, RE power 300 W, DCbias 200 V, Ar flow 50 sccm, etching time 1 min and pressure 10 mTorr.The plasma etching rate was determined by measuring the thickness (T0)of the organic protection layer before plasma treatment and thethickness (T1) of the organic protection layer after treatment andcalculating the plasma etching rate according to Eq. 1, and the resultsthereof were shown in Tables 1 to 3:Plasma etching rate(nm/min)=(T0−T1)/M  [Equation 1]

(2) Surface roughness (nm): The specimen prepared as described above inevaluation of physical property (1) was placed on an atomic forcemicroscope (XE-100, Park systems), and a surface roughness wasdetermined by setting a Head Mode to contact Mode, and a PSPD DisplayWindow to A+B→1V, A-B→−500 mV to +500 mV.

(3) Color coordinate YI (ASTM D1925): Transmittance was measured on thespecimen prepared as described above in evaluation of physical property(1), at a wavelength of 300 nm to 800 nm using an UV-visiblespectrophotometer (UV-2450, SHIMADZU) analysis equipment followed by thecalculation of a color coordinate YI (ASTM D1925).

(4) Light transmittance (%): Total transmittance was measured on thespecimen prepared as described above in evaluation of physical property(1), at a wavelength of 400 to 700 nm using a hazemeter (NDH-5000,Nippon Denshoku) according to ASTM D1003-95 5.

TABLE 1 Examples (Unit: pbw) 1 2 3 4 5 6 7 8 9 10 11 12 13 (A) (a1) 9080 70 60 60 60 — — — — — 60 60 (a2) — — — — — — 60 50 — — — — — (a3) — —— — — — 20 — 30 30 — — — (a4) — — — — — — — 20 30 30 60 — — (B) (b1) 1020 30 40 — — 20 30 — — — — — (b2) — — — — 40 — — — 40 — 20 — — (b3) — —— — — 40 — — — 40 20 — — (b4) — — — — — — — — — — — 40 — (b5) — — — — —— — — — — — — 40 (b6) — — — — — — — — — — — — — (b7) — — — — — — — — — —— — — (b8) — — — — — — — — — — — — — (b9) — — — — — — — — — — — — —(b10) — — — — — — — — — — — — — (C) 5 5 5 5 5 5 5 5 5 5 5 5 5 Plasmaetching rate 385 364 357 331 328 342 353 341 320 336 326 325 342(nm/min) Surface roughness 1.24 1.33 1.52 1.83 1.86 1.65 1.44 1.64 1.871.73 1.74 1.83 1.54 Color coordinate YI 0.41 0.41 0.41 0.41 0.4 0.420.41 0.41 0.42 0.42 0.41 0.41 0.41 Light transmittance 99 99 99 99 99 9999 99 99 99 99 99 99 (%)

TABLE 2 Examples (Unit: pbw) 14 15 16 17 18 19 20 21 22 23 24 25 (A)(a1) 60 — — — — — 60 60 60 60 — — (a2) — 50 — 60 — 30 — — — — 70 — (a3)— — 30 — 70 — — — — — — 70 (a4) — 20 30 — — 30 — — — — — — (B) (b1) — —— — — — — — — — — 20 (b2) — — — — — — — — — — — — (b3) — — — 20 — — — —— — — — (b4) — 30 — — 20 — 35 35 35 35 — — (b5) — — 40 20 — 20 — — — —20 — (b6) 40 — — — 10 20 — — — — — — (b7) — — — — — — 5 — — — — — (b8) —— — — — — — 5 — — 10 — (b9) — — — — — — — — 5 — — — (b10) — — — — — — —— — 5 — 10 (C) 5 5 5 5 5 5 5 5 5 5 5 5 Plasma etching rate 360 340 335338 348 328 323 320 320 321 354 352 (nm/min) Surface roughness 1.74 1.641.68 1.53 1.74 1.52 1.83 1.82 1.83 1.82 1.63 1.64 Color coordinate YI0.43 0.42 0.41 0.41 0.42 0.42 0.42 0.42 0.42 0.42 0.42 0.42 Lighttransmittance 100 99 99 99 99 99 99 99 99 99 99 99 (%)

TABLE 3 Comparative Examples (Unit: pbw) 1 2 3 4 5 6 7 8 9 10 11 12 1314 15 (A) (a1) 100 50 60 95 — — — — — — 50 — — 30 — (a2) — — 40 — 40 — —50 — — — — 30 — — (a3) — — — 5 — 20 — — 30 — — 50 — — 50 (a4) — — — — —20 40 — — 40 — — 20 20 — (B) (b1) — 50 — — 60 — — — — — — — — — 30 (b2)— — — — — — 30 20 — — — — — — — (b3) — — — — — 60 30 — — — — — — — —(b4) — — — — — — — 30 40 — — — — — — (b5) — — — — — — — — 30 30 — — 30 —— (b6) — — — — — — — — — 30 — 30 — 30 — (b7) — — — — — — — — — — 50 20 —— — (b8) — — — — — — — — — — — — 20 — — (b9) — — — — — — — — — — — — — —20 (b10) — — — — — — — — — — — — — 20 — (C) 5 5 5 5 5 5 5 5 5 5 5 5 5 55 Plasma etching rate 418 327 610 820 280 314 308 312 296 310 324 318287 320 322 (nm/min) Surface roughness 1.14 2.16 1.24 1.22 3.42 2.433.13 2.24 3.35 3.14 2.54 2.43 3.65 2.44 2.42 Color coordinate YI 0.410.41 0.41 0.41 0.45 0.46 0.44 0.41 0.41 0.43 0.46 0.45 0.48 0.45 0.45Light transmittance 99 99 99 99 99 99 99 99 99 100 99 99 95 99 99 (%)

In the result of Tables 1 to 3, it is shown that the composition had lowplasma etching rate and thus remarkably excellent plasma resistance, anda surface roughness value of 2 nm or less and thus excellent smoothnessin Examples. Further, it is apparent that the composition had colorcoordinate YI (ASTM D1925) of less than 0.50 and high lighttransmittance, thus providing the transparent organic protection layer.Meanwhile, there were problems such as high etching rate and surfaceroughness in Comparative Examples relative Examples.

Many modifications and other embodiments of the present invention willcome to mind to one skilled in the art to which this invention pertainshaving the benefit of the teachings presented in the foregoingdescription. Therefore, it is to be understood that the invention is notto be limited to the specific embodiments disclosed and thatmodifications and other embodiments are intended to be included withinthe scope of the appended claims.

The invention claimed is:
 1. A composition for display sealing material,the composition comprising a photo-curable monomer and aphotopolymerization initiator, wherein: the photo-curable monomerincludes a first monomer and a second monomer, the first monomer notcontaining an aromatic hydrocarbon group and not containing a C3 to C20cycloalkyl group; and the second monomer containing two or more ofsubstituted or unsubstituted phenyl groups, represented by Formula 1,the first monomer includes at least one of a mono(meth)acrylate havingan amine group, a di(meth)acrylate having a substituted or unsubstitutedC1 to C20 alkylene group that does not include a C2 to C30heterocycloalkyl group, a di(meth)acrylate having an ethylene oxidegroup, and a tri(meth)acrylate having an ethylene oxide group, and thesecond monomer is present in an amount of from about 10 wt % to about 40wt % in the photo-curable monomer, and the first monomer is present inan amount of from about 60 wt % to about 90 wt % in the photo-curablemonomer:

wherein, in Formula 1, A is a hydrocarbon having two or more ofsubstituted or unsubstituted phenyl groups, or a hydrocarbon having aheteroatom and two or more of substituted or unsubstituted phenylgroups; Z¹ and Z² are each independently represented by Formula 2; and aand b are an inter of 0 to 2, respectively, and a+b is an inter of 1 to4;

wherein, in Formula 2, * represents a linker site to a carbon atom on A;X is a single bond, O, or S; Y is a substituted or unsubstituted C1 toC10 linear alkylene group, or a substituted or unsubstituted C1 to C20alkoxy group, R¹ is a hydrogen or a C1 to C5 alkyl group; and c is 0or
 1. 2. The composition for display sealing material according to claim1, wherein the second monomer includes at least one of amono(meth)acrylate and a di(meth) acrylate.
 3. The composition fordisplay sealing material according to claim 2, wherein: the secondmonomer includes the mono(meth)acrylate, and the mono(meth)acrylate isrepresented by Formula 3:

wherein, in Formula 3, R² is hydrogen or a methyl group, R³ is asubstituted or unsubstituted linear C1 to C10 alkylene group, or asubstituted or unsubstituted C1 to C20 alkoxy group, and R⁴ is ahydrocarbon having two or more of substituted or unsubstituted phenylgroups, or a hydrocarbon having a heteroatom and two or more ofsubstituted or unsubstituted phenyl groups.
 4. The composition fordisplay sealing material according to claim 2, wherein: the secondmonomer includes the di(meth)acrylate, and the di(meth) acrylate isrepresented by Formula 4:

wherein, in Formula 4, R⁵ and R⁹ are hydrogen or a methyl group, R⁶ andR⁸ are each independently a substituted or unsubstituted linear C1 toC10 alkylene group, or a substituted or unsubstituted C1 to C20 alkoxygroup, and R⁷ is a hydrocarbon having two or more of substituted orunsubstituted phenyl groups, or a hydrocarbon having a heteroatom andtwo or more of substituted or unsubstituted phenyl groups.
 5. Thecomposition for display sealing material according to claim 1, whereinthe second monomer includes at least one of4-(meth)acryloxy-2-hydroxybenzophenone,ethyl-3,3-diphenyl(meth)acrylate, benzoyloxyphenyl (meth)acrylate,bisphenol A di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate,bisphenol F di(meth)acrylate, ethoxylated bisphenol F di(meth)acrylate,4-cumylphenoxyethylacrylate, 2-phenylphenoxyethyl (meth)acrylate,2,2′-phenylphenoxyethyl di(meth)acrylate,2-phenylphenoxypropyl(meth)acrylate, 2,2′-phenylphenoxypropyldi(meth)acrylate, 2-phenylphenoxybutyl(meth)acrylate,2,2′-phenylphenoxybutyl di(meth)acrylate, 2-(3-phenylphenyl)ethyl(meth)acrylate, 2-(4-benzylphenyl)ethyl (meth)acrylate,2-phenyl-2-(phenylthio)ethyl (meth)acrylate, 2-(triphenylmethyloxy)ethyl(meth)acrylate, 4-(triphenylmethyloxy)butyl(meth)acrylate,3-(biphenyl-2-yloxy)butyl(meth)acrylate,2-(biphenyl-2-yloxy)butyl(meth)acrylate,4-(biphenyl-2-yloxy)propyl(meth)acrylate,3-(biphenyl-2-yloxy)propyl(meth)acrylate,2-(biphenyl-2-yloxy)propyl(meth)acrylate,4-(biphenyl-2-yloxy)ethyl(meth)acrylate, 3-(biphenyl-2-yloxy)ethyl(meth)acrylate, 2-(4-benzylphenyl)ethyl(meth)acrylate,4,4′-di(acryloyloxymethyl)biphenyl, 2,2′-di(acryloyloxyethoxy)biphenyl,structural isomers thereof, or mixtures thereof.
 6. The composition fordisplay sealing material according to claim 1, wherein the hydrocarbonhaving two or more of phenyl groups, or a hydrocarbon having aheteroatom and two or more of substituted or unsubstituted phenyl groupsincludes a substituted or unsubstituted biphenyl group, a substituted orunsubstituted triphenylmethyl group, a substituted or unsubstitutedterphenyl group, a substituted or unsubstituted biphenylene group, asubstituted or unsubstituted terphenylene group, a substituted orunsubstituted quaterphenylene group, a substituted or unsubstituted2-phenyl-2-(phenylthio)ethyl group, a substituted or unsubstituted2,2-diphenylpropane group, a substituted or unsubstituteddiphenylmethane group, a substituted or unsubstituted cumyl phenylgroup, a substituted or unsubstituted bisphenol F group, a substitutedor unsubstituted bisphenol A group, a substituted or unsubstitutedbiphenyloxy group, a substituted or unsubstituted terphenyloxy group, asubstituted or unsubstituted quaterphenyloxy group, a substituted orunsubstituted quinquephenyloxy group, and the like.
 7. The compositionfor display sealing material according to claim 1, wherein the secondmonomer has a weight average molecular weight of about 100 g/mol toabout 1000 g/mol or less.
 8. The composition for display sealingmaterial according to claim 1, wherein the photo-curable monomer isconsisted of only an element selected from C, H, O, N and S.
 9. Thecomposition for display sealing material according to claim 1, whereinthe photopolymerization initiator is at least one of triazine,acetophenone, benzophenone, thioxanthone, benzoin, phosphorus, and oximeinitiator.
 10. The composition for display sealing material according toclaim 1, further including a thermal stabilizer.
 11. The composition fordisplay sealing material according to claim 10, wherein the thermalstabilizer is present in an amount of about 100 ppm to about 1000 ppm,on the solid contents, in the composition for display sealing material.12. A display apparatus including: a display member; and a compositeprotection layer formed on the display member, wherein: the compositeprotection layer includes a inorganic protection layer and an organicprotection layer, and the organic protection layer includes a curedproduct prepared of the composition for display sealing materialaccording to claim
 1. 13. The display apparatus according to claim 12,wherein: the inorganic protection layer includes at least one selectedfrom metal, oxides of the metal, fluorides of the metal, nitrides of themetal, oxynitrides of the metal, borides of the metal, oxyborides of themetal, and silicides of the metal, and the metal includes at least oneselected from silicon (Si), aluminum (Al), selenium (Se), zinc (Zn),antimony (Sb), indium (In), germanium (Ge), tin (Sn), bismuth (Bi),transition metal, and lanthanide metal.
 14. The display apparatusaccording to claim 12, wherein the display member is a light emittingdiode (LED), an organic light emitting diode (OLED), an OLED lightinstrument or a LED light instrument.
 15. The composition for displaysealing material according to claim 1, wherein the first monomerincludes 2-aminoethyl (meth)acrylate, 2-dimethylaminoethyl(meth)acrylate, octanediol di(meth)acrylate, nonanedioldi(meth)acrylate, decanediol di(meth)acrylate, undecanedioldi(meth)acrylate, dodecanediol di(meth)acrylate, ethylene glycoldi(meth)acrylate, triethylene glycol di(meth)acrylate,trimethylolpropane tri(meth)acrylate, or mixtures thereof.